Presently, people are suffering from various diseases such as cancer, weakened immunity, adult diseases, gastrointestinal diseases, hypertension, diabetes, cardiovascular diseases and fatigue accumulation, due to polluted atmosphere quality and westernized dietary, drinking, stress, irregular meals and the like. Accordingly, as interest in the prevention and treatment of the above diseases increases, demand of health functional food therefor is also increasing. In particular, recently, interest in vitamins, mineral preparations, as well as food processed from natural materials without side effect even in long-term use, or health functional food using a natural material extract is more increasing.
Among the effective components of this health functional food, attention is especially drawn to saponin. Saponin is a generic name of triterpene or steroid-based glycoside distributed in the vegetable kingdom, and a natural surfactant substance having a bubbling characteristic. Saponin is commonly known as an effective component of ginseng and red ginseng, but also present in many plants such as beans, spring onion, deodeok, balloonflower, water dropwort, garlic, onion and kadzu, and also contained in Akebia quinata seeds in a large amount. Saponin has a function to decrease cholesterol and increase immunity, and is known to represent various pharmacological active effects such as prevention and treatment of cardiovascular diseases, an immunity enhancement effect, an anti-cancer effect, inflammation relief, diabetes inhibition, prevention of atherosclerosis and hypertension, liver function promotion, fatigue recovery, antioxidant activity and anti-inflammatory activity.
Akebia quinata is a vine belonging to Anthophyta class/Ranunculales order/Lardizabalaceae family/Akebia genus, and distributed throughout Korea, Japan, China, etc. The scientific name thereof is akebia quinata, and it is also called Imhabuin (), Moktong () or Tongcho (), and the Akebia quinata fruit is also called Yeonbokja (). It mainly inhabits valleys or gorge, and grows by winding up a neighboring tree, or leaning against a rock. Since its leaves and fruits have an unusual shape, it is also used for landscaping, and its roots, stem and fruits are all edible. It bears fruits in September or October, and the flesh of the fruits has a curved oval shape, a length of 6 to 10 cm, and a very thick skin. It is characterized in that when the fruit is fully ripe, the skin is split so that a white and soft content and black seeds come out. The stem and root are collected during autumn, dried in the shade, and then boiled for drinking tea, and the fruit is collected when ripe during autumn, and used raw, or dried in the shade to be boiled for drinking tea. In addition, young leaves are blanched for eating a seasoned vegetable, and ripe fruits are also eaten as they are.
The stem and roots of Akebia quinata are used as medicinal materials in oriental medicine, and known to have diuretic, antibacterial, and anti-inflammatory effects. The Akebia quinata fruit contains effective components such as saponin and oleanolic acid, and in particular, saponin is more contained in the seed than in the stem or root.
Korean Patent Registration No. 10-0573375 provides a composition having an anticancer activity by utilizing an Akebia quinata seed extract, but saponin contained in the Akebia quinata seed was not sufficiently utilized. Further, the study for utilizing the stem and root of Akebia quinata was actively performed with the influence of oriental medicine, however, the study of the Akebia quinata fruit was insufficient, as compared with the stem or root. Thus, the present inventors improved the saponin extraction efficiency from Akebia quinata seeds by various studies, and have developed functional food by using it.